Medicines & Supplements A to Z > Norethisterone


Last updated on 03/08/2021.

Overview   |   Dosage   |    Side Effects   |   Precautions  |   Tips  |   Where To Buy NAME: Norethisterone




DRUG CLASS: Endocrine drugs

SUB CLASS: Progestins

USED FOR: Endometriosis, Abnormal uterine bleeding

– 5mg (tablets)

What is Norethisterone for?

Norethisterone belongs to a class of medications called progestins. It is a synthetic hormone to treat endometriosis and abnormal uterine bleeding.

How to use it?

Norethisterone can be taken orally as tablets.

For endometriosis:
5-10 mg twice daily starting between the 1st and the 5th day of the menstrual cycle, for at least 4-6 months.

For abnormal uterine bleeding:
5 mg three times daily for 10 days. Withdrawal bleeding may be expected within 2-4 days after discontinuing. To prevent recurrence of heavy bleeding, administer 5 mg twice daily on days 19-26 of the two subsequent cycles.

What are the side effects of Norethisterone?

Common side effects of Norethisterone include nausea, dizziness, headache, breast tenderness, or irregular periods.

Who should not take Norethisterone?

– People who are allergic to Norethisterone or any component of the formulation
– Patients with known, suspected, or history of breast cancer or sex hormone-dependent cancers
– Pregnant or breastfeeding women
– Patients with diabetes
– Patients with current or history of thromboembolic diseases
– Patients with undiagnosed abnormal vaginal bleeding or untreated endometrial hyperplasia

Pharmacist Tips:

– Do not smoke during treatment, as it may increase the risk of cardiovascular side effects.
– Norethisterone 5 mg is not used for contraception, so you should use effective contraception during treatment. If you have any signs of pregnancy, seek medical help immediately.

Common dosing schedule:
Norethisterone should be at the same time each day, with or without food.

This schedule is for reference only, adjustments may be made according to individual needs.

Some common medications Norethisterone may interact with:
St John’s Wort
– Protease inhibitors, e.g. Ritonavir, Darunavir
– Anticonvulsants, e.g. Carbamazepine, Phenytoin
– Anticoagulants, e.g. Warfarin, Dabigatran 

Please notify your doctor or pharmacist if you are taking the above medication, dosage adjustments might be needed.

Where to buy Norethisterone in Hong Kong?

In Hong Kong, Norethisterone is a prescription only medicine, and requires a prescription from a doctor to be purchased in a pharmacy. It can also be obtained from doctors. To find a pharmacy near you, refer to the list of pharmacies (“Authorized Sellers of Poisons”) from the Hong Kong Department of Health.

For more information about drug names and ingredients, you can visit Hong Kong’s Drug Office at

Need more information?

For detailed information about the use of Norethisterone in children, pregnancy and breastfeeding, and for questions about drug interactions, please check with your pharmacist or doctor.

Disclaimer: our goal is to provide you with the most relevant drug information and common dosage for Hong Kong. This information does not constitute medical advice. For specific treatment recommendations and advice, always discuss with your doctor or pharmacist, and follow the instructions included with your specific medicine.